Rookie wide receiver Deebo Samuel had plenty to keep him busy as he prepared for his first 49ers regular-season game with a cross-country flight to Tampa, Florida.

As he packed his bags Friday for a nine-day trip, Samuel said his mind was on the work ahead of him -- and not his NFL debut.

“I feel very comfortable,” Samuel said. “I’m still studying. When I get on the plane I still have stuff to do. When game time comes, I feel like I’m going to be well-prepared.

“I try to stay calm until Sunday morning -- maybe Saturday night.”

The 49ers’ season opener on Sunday against the Tampa Bay Buccaneers comes with a lot of question marks. Near the top of the list of unknowns is which wide receiver will emerge as a reliable target for quarterback Jimmy Garoppolo.

Samuel is a good guess.

“That’s going to be interesting as we go through each game,” 49ers coach Kyle Shanahan said. “That’s something that isn’t set and it depends on the play called and the personnel in.”

The 49ers have not identified their starting receivers among a group that consists of Samuel, Dante Pettis, Kendrick Bourne, Marquise Goodwin and Richie James. Those five receivers are expected to be active for the game on Sunday with Trent Taylor and Jalen Hurd ruled out due to injuries. Shanahan said each of the team's active receivers will have a role in Week 1.

Samuel was not unleashed in the preseason, though he ranked second on the 49ers with six receptions for 104 yards. The 49ers coached Samuel at the Senior Bowl, where they witnessed his playmaking ability and tough, determined running style after the catch.

Samuel said he likes the team’s game plan to go up against the Buccaneers, but has not wasted any energy on projecting what it might mean for his stat line on Sunday.

“I just go out and contribute to the team in any aspect of the game,” he said. “I don’t set personal goals. I just go out there and do what I got to do.”

Number of wide receivers on final 49ers' 53-man roster 'up in the air'

Number of wide receivers on final 49ers' 53-man roster 'up in the air'

SANTA CLARA — When looking at which wide receivers will make the 49ers' final 53-man roster, it appears that the choice for the final spot could be between Kendrick Bourne and Jordan Matthews.

Bourne finished the 49ers' 27-24 loss to the Chargers with one completion on three targets for a touchdown. Unfortunately for Bourne, the score came after dropping a pass from C.J. Beathard that hit him in the hands.

49ers coach Kyle Shanahan has mentioned repeatedly that he is looking for consistency from his receiving corps. While Bourne has improved from last year, he still has a lot to prove to the coaching staff.

“That’s not the most consistent right there but drops from Bourne haven’t been too much of a problem.” Shanahan said. “I do consider Bourne having some of the better hands on our team, so that’s definitely one that he should have had, and it hurt a drive. I think we went three-and-out on that drive but he’s earned a little bit more with that in terms of how good his hands are."

After the game Bourne expressed disappointment about the drop, but was confident about the remainder of his play in the game.

“I felt good about it, but want that drop back,” Bourne said. “Felt good on special teams too. I could have done better like always, but I felt good with how much time I had to play.”

Special teams are something that Matthews has not done a lot of, but he understands that it could help him earn a spot on the roster. He was the gunner facing the Chargers, something hasn’t done since he his college days at Vanderbilt.

“I don’t think since I was a freshman at Vandy,” Matthews said. “But I worked in practice some when I was in New England and some with the Eagles. It’s really been mostly practice but I got some game reps when we were in Denver so it’s not new as far as game speed.”

Over four games, Matthews finished the preseason catching three of his five targets for 45 yards. Shanahan has said that Matthews is a known quantity that doesn’t need to prove what he is capable of on the field but he has challenged him on special teams.

“I feel like it’s natural for a receiver to just come off the line, getting out of a jam,” Matthews said. “And then I played free safety in high school so tackling isn’t like a hard thing, tracking, and going and bringing a guy down is not overwhelming to me.”

After the game Shanahan confirmed that the decisions at wide receiver didn't get much clarity especially with rookie Jalen Hurd’s uncertain availability in Week 1 against Tampa Bay.

“It’s not,” Shanahan said. “There’s a lot of things up in the air, especially with some of these injuries that have been a little more serious that we’ve found out over the last week than we thought previously.

“It still is up in the air. We’ve got to decide on whether we’re going to go with six, whether we’re going to go with seven and it’s something we are going to be looking into hard over these next 48 hours.”

49ers takeaways: What we learned in 27-24 preseason loss to Chargers

49ers takeaways: What we learned in 27-24 preseason loss to Chargers

SANTA CLARA – The 49ers wrapped up the preseason with a 27-24 loss to the Los Angeles Chargers at Levi’s Stadium.

The world will little note, nor long remember what occurred Thursday night, as the 49ers sat out more than 30 players. But, nonetheless, here are three takeaways from the festivities:

Beathard shows blocking skills

Quarterback C.J. Beathard got the start on Thursday but likely is behind Jimmy Garoppolo and Nick Mullens on the team’s depth chart.

Coach Kyle Shanahan stated last week that he plans to keep three quarterbacks on the regular-season roster, but that remains to be seen. Beathard distinguished himself in his first two NFL seasons for his toughness.

He showed some of those qualities as he ran 20 yards down the field to make a block on Chargers cornerback Brandon Facyson to help spring running back Jeff Wilson on a 41-yard touchdown run.

Beathard played the entire first half before Mullens replaced him at the start of the third quarter. He completed 6 of 9 pass attempts for 58 yards with a touchdown, no interceptions and a passer rating of 121.5.

Mullens played just one series, completing 1 of 3 pass attempts for 13 yards. Undrafted rookie Wilton Speight played the rest of the way.

Decisions on the defensive line

Third-year pro D.J. Jones appears to have a roster spot locked down, based on the team’s decision to keep him out of action against the Chargers.

Some of the other defensive linemen face uncertain futures, though. Sheldon Day, Jullian Taylor and Damontre Moore were among the veteran defensive lineman who suited up and saw action. Moore had four tackles and a quarterback hit.

The 49ers also held out DeForest Buckner, Arik Armstead, Solomon Thomas and Dee Ford. Nick Bosa remained out with an ankle injury sustained on Aug. 7. The 49ers believe there is a chance Bosa could be available for the regular-season opener on Sept. 8 against the Tampa Bay Buccaneers.

Bourne vs. Matthews?

Most of the spots at wide receiver appear set with six players standing above the rest: Dante Pettis, Deebo Samuel, Marquise Goodwin, Jalen Hurd, Trent Taylor and Richie James. Taylor is expected to miss some games due to recent foot surgery and Hurd’s availability is in question due to a back condition. The 49ers are likely to keep a seventh wideout to open the season.

It could come down to Kendrick Bourne and Jordan Matthews for the final spot. Bourne and Matthews were in uniform, and both had a significant role on special teams, too.

The major knock on Bourne has been his consistency. Those ups and downs were on full display Thursday night. He did not help himself in the second quarter when he dropped a pass from Beathard on a crossing pattern.